Swimming appliance



H. E. CRUM SWIMMING APPLIANCE Nov. 27, 1956- 5 S heetS-SiiQet 1 FiledJan. 11, 1954 HA nvgr E. cRuM, mmvnm.

A T TORNEK MW. 27, 1956 M. 2,771,618

SWIMMING APPLIANCE 3 Sheets-Sheet 2 Filei Jan. 11. 1954 HARVEY E- CRUM,

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, swmumc APPLIANCE Filed Jan. 11, 1954 3 Sheets-Sheet 3 HARVEY E. CRUMyIN V EN TOR.

A TTORNEK United States Patent SWIMMING APPLIANCE Harvey E. Crum, SantaMonica, Calif.

Application January 11, 1954, Serial No. 403,310

1 Claim. (Cl. 9-21) This invention relates to a swimming applianceparticularly adapted to be worn on the swimmers forearm to assist in thepropulsion of the body through the water.

Many devices of this general character have been known; however, noneprior to my invention has been satisfactory, especially with respect tofacility of operation in opening easily to provide a fin for the forwardstroke and closing easily to avoid resistance of the fin on the returnstroke during swimming.

In accordance with my invention, however, I provide a device which canreadily and satisfactorily be applied to the forearm and which will openreadily on the swimming stroke to provide a fin to assist propulsion andwill readily fold to avoid resistance on the return stroke. The deviceof my invention is moreover relatively simple and direct and effectivein its operation.

In general, in accordance with the preferred embodiment of my inventionit comprises an elongated body structure adapted to be fitted along thelower portion -of the forearm by means of a cuff extending from saidbody structure and adapted to be laced about and at the top of theextended forearm (with the back of the hand upward as in a swimmingstroke). Extending from each side of the body structure are meansmovably mounted upon the body structure to support a fin or webbing andadapted to hold the webbing outward in extended position during aswimming stroke and to fold or retract the webbing on the return stroke.

In order to illustrate my invention there is shown in the drawings aspecific embodiment thereof which will be described taken in conjunctionwith the accompanying drawings in which: a

Fig. 1 is a diagrammatic functional view of the use of my improvedswimming device showing one attached to each arm, the right armillustrating the opened position of the fins during the backwardpropelling stroke, the left arm illustrating the folded or contractedposition of the fins during the forward reach.

Fig. 2 is a sideview of my swimming device showing it, in its foldedposition, attached to the arm.

Fig. 3 is a plan view of the device showing it, in its expandedposition, attached to the arm.

Fig. 4 is a side view of the device showing it, in its expandedposition, attached to the arm.

Fig. 5 is a plan view of the device showing it in its folded position.

Fig. 6 is a section view on the line 66, Fig. 3.

Fig. 7 is a detail plan view showing how the ribs of the fin areattached to the underside of the body structure.

Fig. 8 is a detail view of a portion of Fig. 6 showing, in detail, howthe ribs or" the fin are movably mounted to the body structure.

in accordance with the specific embodiment of my invention hereillustrated an elongated central body structure 1, which is light,substantially thin and flat and as shown most clearly in Figures 4, 6, 7and 8 is adapted to be affixed to the forearm 2 of the swimmer by meansof a cufi 3 of flexible material, preferably elastic cloth, attached tothe body structure and adapted to be laced about and at the top of theforearm by laces 4. Extending outward and somewhat downwardly from eachside of the elongated body structure 1 are ribs 5, 6, 7 and 8 extendingto the right and ribs 5', 6', 7' and 8' extending to the left, as shownin Fig. 3. Extending between each rib and between the two sets of ribs5, 6, 7 and 8 and 5, 6, 7' and 8 and under the body structure 1 is awebbing 9, preferably of flexible material such as sheet rubber.

As will be explained in more detail below, ribs 5, 6, 7 and 8 and 5, 6',7 and 8 are movably mounted to the elongated central body structure 1 tomove from the extended position shown in Fig. 3 to the folded positionshown in Fig. 5. The webbing 9 is afiixed to ribs 5 and 5 by overlappingend flaps 10 and 10 of the webbing which extend around and on top ofribs 5 and 5' and are afiixed to the overlapping portion of the webbingby a suitable adhesive. Webbing 9, as viewed in Fig. 3, extendsunderneath ribs 6, 7, 6 and 7', and is fastened to ribs 8 and 8 byoverlapping end flaps 11 and 11'. The webbing 9 is afiixed to ribs 6, 7,6' and 7' at the ends by an overlapping portion of the webbing 12 and12' which is affixed over the ends of the ribs by a suitable adhesive.The webbing is movably supported to ribs 6, 7, 6' and 7' by small strips13, 14, 13' and 14 extending over the respective ribs and aflixed to thewebbing by means of adhesive. Strips 13, 14, 13' .and 14' are preferablyso affixed to the respective ribs 6, 7, 6 and 7' that with the expandingand folding of the webbing the webbing may move slightly with respect tothe ribs; that is, the web and the strip may move slightly along therib. This allows flexibility of the web in moving from the expanded tothe folded position and return. The webbing is preferably made offlexible material such as rubber to permit stretching between suchpoints as A and B on Fig. 3 as the ribs move from the fully expandedposition to the folded position.

The webbing 9 is so aflixed and of such shape that in the fully expandedposition shown in Fig. 3 with the ribs fully extended the webbing isfairly taut especially between the ribs to provide a fin for theswimming stroke but slightly loose in the region under the arm andelongated body structure. Under the arm and body structure the webbingis free and not supported to the body structure or the ribs exceptpreferably at the front end of the body structure as shown at 15 in Fig.7. Here the webbing is attached to the front end of the body structureby a piece 15 to avoid the entry of most of the water between the weband the elongated body member 1 on the part of the return stroke.However, the region 15 is cut away to allow free movement of ribs 5 and5' back and forth. Also, at this point, the webbing is loose to permitthe free movement of ribs 5 and 5' from folding to extended position.

As shown most clearly in Figures 6, 7 and 8, each of the ribs extendoutwardly and downwardly at an angle from the horizontal as showngenerally in Fig. 6. With this arrangement the ribs hold the web outwardand substantially in somewhat of a cup to act as a fin which will notdouble back under the force of the water during a swimming stroke. Eachrib is movably mounted to the elongated central body structure 1 forlimited relative movement with respect thereto as shown in detail inFigures 7 and 8. Each rib has a spherical end portion 16 which fits intoa corresponding spherical indentation 17 formed within the bodystructure 1 and is rotatably held therein by means of a metal cap member18 having a cup member 19 of spherical configuration on the inside toconform to the spherical end portion 16 of the rib. This forms what maybe termed a cup and ball ge. Metal cap 18 is affixed to 'the under sideof the elongated central body structure 1 by rivets 20 through holes 21in a flat portion 22 of the metal cap member -18. Spherical end -16 isthus rotatable between cup 19 and the spherical indentation 17.

The 'rib'is restricted in its downward movement by the end 23 of-cupmember 19 but may be moved back and forth substantially in the plane ofthe set of four ribs on any one side of the body portion; backward untilthe rib extending from the spherical end 16 contacts the back part 24 ofthe metal cap 18 in its backward motion and forward until the ribcontacts the front 25 of the-metal cap in its forward motion. Torestrict the movement of the ribs upwardly, the two sides of bodystructure I extend downwardly as shown at 26 and 27 in Figures 6 and 8.Thus, it will be seen that each rib ismovably mounted to the bodystructure 1 to permit movement of the rib from the extended portionshown in Figure 3 to the folded portion shown in Fig. while .each rib issubstantially restrained from movement up or down out of a planesubstantially corresponding with the four ribs of any set except for avery slight motion up or down to allow a little flexibility.

Each downwardly extending side 26 and 27 of the body member 1 is formedto have an inclined edge for each rib along which the rib slides whenwater presses against .the web and the web presses against the ribs.Thus, each rib as it moves backward and forward may slide along and isrestricted in its upward movement by an inclined edge 28 with one suchedge for each rib. The forward movement of each rib, however, isrestricted by stops in the form of notches 29, one for each rib. Thus,as the ribs move back and forth from the extended position to the foldedposition they contact stops 29 in the fully extended position and in thefully folded position as shown in Fig. 2 the ribs move underneath andslightly away from the down turned edges 26. In the downward swimmingstroke, as pressure of the water against the web is applied upwardlyagainst the ribs, they are moved forward, because they tend to slide onthe inclined edges '28 into the position against the notches or stops29. This tends to move the ribs into the fully extended position. On thereturn stroke the ribs all move'backward and fold the web as shown inFigures 2 and 5, because on the return stroke the water pressure isapplied substantially in the direction shown by arrow C in Fig. 2.

My device is shown in use on both arms in Fig. 1 where on the leftforearm 30 a device'in accordance with my invention is shown generallyretracted as the left arm is being moved forward just prior to adownward stroke. The right arm 31 is shown near the end of a swimmingstroke with the device in accordance with my invention fully extendedprior to the return stroke.

A single lace 4 may be fastened at 35 so that the lacing may be effectedwith the free arm. Another lace 36 may be attached to body member 1 asat 37, which lace is adapted to be wrapped around the folded device -butnot in use.

In operation my device may be worn on the forearm of the swimmer. On theswimming stroke under the pressure of the water against the webbing 9the fin will open to the fully extended position. This is especially sobecause the pressure of the water against the web pushes the supportingribs against the inclined edges 28 so that in effect the ribs are forceddown these inclined edges to a position against the stops 29. Thisprovides a strong fin of substantial area for propulsion. On the returnstroke the arm moves through the Water as in Fig. 2 so the water pusheson the device in the direction of the arrow C in,-Fig. 2 to cause theweb to fold and avoid the resistance of the fin on the return stroke.Each rib is so arranged and movably mounted that the webbing willreadily fold with the position shown in Fig. 5,. with each of the ribssubstantially above one another. However, as soon as the arm starts in apropulsion stroke, the fin opens immediately to provide a swimming fin.

Having thus described my invention, I claim:

A swimming appliance comprising an elongated substantially fiat memberadapted to be affixed lengthwise to the under portion of the forearm ofa swimmer, an elongated flexible cuff affixed lengthwise to the top ofsaid member and adapted to be laced on to said forearm, ribs movablymounted to the underside of and extending downwardly at a small anglefrom the horizontal from each side of said elongated member and adaptedto support a web affixed to the outer edges of said ribs and adapted tomove substantially in a plane of a set of said ribs on each side of saidelongated member forwardly to an expanded position and backwardly to afolded position, a web forming a fin extending from the outer edges ofsaid ribs underneath said elongated means, said web adapted to flex andribs adapted to move and together expand and form a fin under thepressure of water thereagainst in a downward swimming stroke and toretract and fold to avoid resistance on a return swimming stroke, saidelongated substantially flat member having downwardly extending edges oneach side thereof extending toward said ribs with each of saiddownwardly extending edges having an inclined edge corresponding to eachrib so that said rib can ride down the incline thereof when said rib isplaced thereagainst under the pressure of a downward swimming stroke.

References Cited in the file of this patent UNITED STATES PATENTS1,202,083 Mee Oct. 24, 1916 1,430,600 Snapp Oct. 3, 1922 1,779,590Eilers Oct. 28, 1930 1,908,184 Richmond May 9, 1933 FOREIGN PATENTS180,713 Switzerland Jan. 16, 1936 333,499 Great Britain Aug. 14, 1930

